Gadolinium-modulated 19F signals from perfluorocarbon nanoparticles as a new strategy for molecular imaging.
Recent advances in the design of fluorinated nanoparticles for molecular magnetic resonance imaging (MRI) have enabled specific detection of (19)F nuclei, providing unique and quantifiable spectral signatures. However, a pressing need for signal enhancement exists because the total (19)F in imaging voxels is often limited. By directly incorporating a relaxation agent, gadolinium (Gd), into the lipid monolayer that surrounds the perfluorocarbon (PFC), a marked augmentation of the (19)F signal from 200-nm nanoparticles was achieved. This design increases the magnetic relaxation rate of the (19)F nuclei fourfold at 1.5 T and effects a 125% increase in signal--an effect that is maintained when they are targeted to human plasma clots. By varying the surface concentration of Gd, the relaxation effect can be quantitatively modulated to tailor particle properties. This novel strategy dramatically improves the sensitivity and range of (19)F MRI/MRS and forms the basis for designing contrast agents capable of sensing their surface chemistry.
Neubauer
Anne M
AM
C-TRAIN Group, Washington University, St Louis, Missouri 63108, USA.
Myerson
Jacob
J
Caruthers
Shelton D
SD
Hockett
Franklin D
FD
Winter
Patrick M
PM
Chen
Junjie
J
Gaffney
Patrick J
PJ
Robertson
J David
JD
Lanza
Gregory M
GM
Wickline
Samuel A
SA
D003287:Contrast Media / Q000737:chemistry; D005462:Fluorine Radioisotopes / Q000737:chemistry*; D005466:Fluorocarbons / Q000737:chemistry; D005682:Gadolinium / Q000737:chemistry*; D007089:Image Enhancement / Q000379:methods; D008279:Magnetic Resonance Imaging / Q000379:methods*; D015336:Molecular Probe Techniques; D053758:Nanoparticles / Q000737:chemistry*
D003287:Contrast Media; D005462:Fluorine Radioisotopes; D005466:Fluorocarbons; D005682:Gadolinium